Every four years, NBC’s Olympic audience is expected to ignore what’s impossible to miss:

What’s going on with the women gymnasts? Are they free-range females? Or are they, as widely suspected and even reported — outside of NBC, of course — systemically growth deprived? After all:

1) Why, in their mid-teens to early 20s, are they almost all tiny? Dad’s shown; he’s about 6-foot. Mom’s shown; she’s 5-4. And their 17-year-old world-class gymnast daughter is 4-11.

Odd, no? For all the smiley face interviews, how do Mom and Dad explain that? How do they feel about it?

2) Why are they so under-developed? Virtually no breasts, no hips, no natural physiological — or just plain logical — progression.

Investigations have included testimonies by former U.S. Olympians that they were so training formula-abused that their menstrual cycles were delayed by years, and that they were so calcium-deficient during normal growth years that they are highly susceptible to bone breaks and other osteopathic issues — and for the rest of their lives.

The famous/infamous coach of the Romanian then U.S. teams of the 1980s and 90s, Bela Karolyi, was later accused by several of his former Olympians of verbal and physical abuse, including insults about their weight, demands to train and compete while injured, and reliance on near-starvation diets that made their bones brittle.

But the successes of Karolyi’s gymnasts seemed to justify, or at least excuse, such methods. And likely perpetuate them.

3) Why do so many have squeaky voices, the voices of 10- to 12-year-olds?

4) Why do so many have chalky, pallid complexions, as if just pulled from a freezer?

Or is all of the above just none of our N-B-C business? Again.

Costas does time-travel dance with tape-delayed events

Bob Costas is doing it again. As primetime host of another “plausibly live” NBC Olympics, he sounds committed to returning from London with his credibility.

He has been carefully able to speak the future in the past tense, which comes in handy when you’re promoting the primetime appearance of events long ago ended.

Thus, when referencing Michael Phelps, Costas said, “He swam,” followed by “and we’ll show you that later on.” It’s as if he’s giving the “hi sign,” a verbal wink that transmits, “You know that I know that you know.”

And in Phelps’ case, “later on” means far deeper into primetime, to hold those in the audience who don’t yet know the result or will watch, regardless.

On the other side of this Olympic coin is NBC’s “Today Show,” which every morning has banged the drums obnoxiously for primetime coverage of events — being held as “Today” is airing!

But “Today” and NBC out-slicked itself last week. It ran a promo identifying USA’s Missy Franklin’s as the winner in the 100 meter backstroke — an event and a result that was to have been held for that night’s primetime.

* The NFL, better late than never, wants to diminish head-hunting, concussions and sick bounty mindsets that would create an ambulance road rally from NFL stadia. Yet, it still wants to sell the NFL as the preferred stop to satisfy the blood lust in bozos.

Incredibly, Ravens’ linebacker Ray Lewis, an unapologetic head-breaker who has been fined in the past — not to mention a fellow who made a cash settlement with the families of the victims in a still-unsolved double homicide in Atlanta in January 2000 — remains an NFL TV and NFL-licensed products go-to sales guy.

* ESPN and ESPN Radio last week lost hoops specialist Doug Gottlieb to the new CBS Sports Radio Network, a real loss in that Gottlieb, though under-utilized and under-cultivated by ESPN, knew — and was unafraid to speak — his stuff.

For all the mock drafts and bracketology ESPN pushes, no one within the network could more succinctly or expertly evaluate talent and the overall college scene — schedules, coaches, strategies — than Gottlieb.

He also has guts. He doesn’t pander to big-time college coaches — even when they’re on the air with him. Armed with facts, he once traded verbal punches with Jim Boeheim, who clearly was unaccustomed to anything but fanny-kissing from TV and radio guys and gals.

ESPN, we’re told, wanted to keep Gottlieb, but in addition to offering more money, CBS will allow him to work from California, where his family lives. With the right partner, he would make a good drive-time host.

Doc a splash with water polo

Doc Emrick calling Olympic water polo is a natural — hockey on a melted pond … NBC’s genuinely live weekday coverage — kiss-off time, in NBC’s scheme — seems predicated on the absence of contending Americans.

* Heaven forbid that Darrelle Revis would report to Jets’ camp wearing a Jets cap, or no cap, or a salary cap. He showed up in a Chicago Bulls cap. But what can a team expect in exchange for a four-year, $46 million contract, that still is not nearly enough.

* Mike Bossy is now heard in a radio ad for a travel agency’s trip to Word War II Battle of the Bulge sites, with a stop in Paris. In the spot he compares his “fight for four Stanley Cups” to the “fight” in the Ardennes. Ugh. The Battle of the Bulge cost 90,000 Allied casualties, 20,000 killed.

* Carlos Delgado, the former Met who spend 12 years with Toronto — mostly as a slugger — is the latest big name linked to Canada-based HGH doc Anthony Galea, once the team doctor of the CFL Toronto Argonauts. Galea, I suspect, could write an interesting book.

* Rod Strickland, 46, a bad act throughout his NBA days, was brought in by John Calipari to provide a cautionary presence to the young (then done) Kentucky basketball team. Strickland was arrested Thursday for driving despite a suspended license (DUI, his fourth).

* Reader/writer/pal Rich Jeffries notes that on July 26 ESPN ran a promo for its Christmas Day NBA lineup. Pregame begins Labor Day.